Structural and ultrastructural characterization of the palatine epithelium of the Guinea pig: A new record of telocytes in the oral cavity.

The morphology of the oral cavity of mammals relates to diet, habitat, and function. The palate is an important region with adaptations for oral somatosensation and mechanical loads due to the pressure of the tongue with food. The research aimed to describe the structural and ultrastructural characteristics of the epithelium and the connective tissue cores of the guinea pig palate using macroscopic, light microscopy, scanning electron microscopy, and transmission electron microscopy analysis. The hard palate had conical and filiform papillae, and the soft palate had open salivary ducts. After the removal of the epithelium, the connective tissue cores revealed thin filaments and laminar projections in the hard palate, and opening ducts were evidenced in the soft palate. The palatine epithelium was keratinized and organized by layers, lamellated corpuscles were found in lamina propria of the hard palate. In contrast, the soft palate had glands clusters associated with nerve fibers, and in both regions were identified telocytes. We concluded that the hard palate presented conical and filiform papillae that differ from other mammals. Besides, it is a new description of the connective tissue cores morphology and the first record of the telocytes in this anatomical region for mammals.

Development of the urinary system in guinea pig females (Cavia porcellus) / Desenvolvimento do sistema urinário em fêmeas de porquinhos-da-índia (Cavia porcellus)

Guinea pigs are animal models widely used in research related to developmental biology. The objective of this work was to demonstrate the process of formation and differentiation of urinary organs in females of the species in the prenatal period. Four females were used at 25, 30, 45 and >65 DG (days of gestation). The animals were dissected, and then macroscopic and microscopic descriptions of the urinary organs were performed. At 25 DG metanephros were present in the urogenital crest into the abdominal cavity. Collecting ducts and glomerular precursor cells could be visualized. After this period, metanephros underwent microstructural modifications to form the kidneys at the end of the prenatal period. After 30 DG, the renal parenchyma already had a cortex, where the glomerulus and proximal convoluted tubules were present; and the medulla, where distal convoluted tubules, collecting ducts, and pelvis were present. The pelvis of each kidney was drained by the ureters. The ureters also underwent tissue differentiation to be differentiated (mucosa with transitional epithelium and lamina propria of connective tissue, muscular, and adventitia) at the end of the prenatal period. The urinary vesicle also underwent tissue changes to form the tunics similar to those found in the ureters, with emphasis on the greater volume of the muscular tunica and the lamina propria that constituted the submucosa in this organ. The pelvic urethra was evidenced by a mucosa lined by transitional epithelium, submucosa, muscular and adventitia. Finally, a partial clitoral urethra and a urethral meatus in the prepuce of the clitoris were also evidenced. The urethral channel began to form with the emergence of the urethral plate and the urethral groove at 30 DG and thereafter with the fusion of the urethral folds to form a partially channeled urethra in the clitoris. A urethral meatus was observed in the most distal portion of the clitoral tissue, formed by the fusion of the prepuce. It is concluded that the urinary organs of guinea pig have similar development to that described in domestic animals, except for the partial clitoral urethra and evident urethral meatus.(AU)

Os porquinhos-da-índia são modelos animais amplamente utilizados em pesquisas relacionadas a biologia do desenvolvimento. O objetivo deste trabalho foi demonstrar o processo de formação e diferenciação dos órgãos urinários em fêmeas da espécie no período pré-natal. Foram utilizadas quatro fêmeas aos 25, 30, 45 e >65 DG (dias de gestação). Os animais foram dissecados e então, realizaram-se descrições macroscópicas e microscópicas dos órgãos urinários. Aos 25 DG os metanefros estavam presentes na crista urogenital da cavidade abdominal. Podiam ser visualizados ductos coletores e células precursoras glomerulares. Após este período, os metanefros sofreram modificações microestruturais para formar os rins ao final do período pré-natal. Após os 30 DG, o parênquima renal já apresentava um córtex, onde estavam presentes os glomérulos e túbulos convolutos proximais, e a medula onde estavam presentes túbulos convolutos distais, ductos coletores e a pelve. A pelve de cada rim era drenada pelos ureteres. Os ureteres também sofreram diferenciação tecidual para estarem com suas túnicas diferenciadas (mucosa com epitélio de transição e lâmina própria de tecido conjuntivo; muscular; e, adventícia) ao final do período pré-natal. A vesícula urinária também passou por modificações teciduais para formar as túnicas semelhantes as dos ureteres, com destaque para o maior volume da túnica muscular e a lâmina própria que constituiu a submucosa neste órgão. Uma uretra pélvica foi evidenciada por uma mucosa revestida por epitélio de transição, submucosa, muscular e adventícia. Por último, uma uretra parcialmente clitoriana e um meato uretral no prepúcio do clitóris também foi evidenciado. O canal uretral começou a se formar com o aparecimento da placa uretral e do sulco uretral aos 30 DG e posteriormente com a fusão das pregas uretrais para formar uma uretra parcialmente canalizada no clitóris. Observou-se um meato uretral na porção mais distal do tecido clitoriano, formado pela fusão do prepúcio. Conclui-se que os órgãos urinários do porquinho-da-índia possuem desenvolvimento semelhante ao descrito em animais domésticos, com exceção da uretra parcialmente clitoriana e do meato uretral evidente.(AU)

Bovine central nervous system development / Desenvolvimento do sistema nervoso central de bovinos

Central nervous system (CNS) development researches are extremely important to the most common congenital disorders and organogenesis comprehension. However, few studies show the entire developmental process during the critical period. Present research can provide data to new researches related to normal development and abnormalities and changes that occur along the CNS organogenesis, especially nowadays with the need for preliminary studies in animal models, which could be used for experimental research on the influence of viruses, such as the influence of Zika virus on the development of the neural system and its correlation with microcephaly in human newborns. Then, present study describes CNS organogenesis in cattle according to microscopic and macroscopic aspects, identifying structures and correlating to gestational period. Fourteen embryos and nine bovine fetuses at different ages were collected and analyzed. All individuals were measured in order to detect the gestational period. Bovine embryo at 17 days age has its neural tube, cranial neuropore, caudal neuropore and somites developed. After 24 days of development, were observed in cranial part of neural tube five encephalic vesicles denominated: telencephalon, diencephalon, mesencephalon, metencephalon and myelencephalon. In addition, the caudal part of neural tube was identified with the primitive spinal cord. The primordial CNS differentiation occurred from 90 to 110 days. The five encephalic vesicles, primordial spinal cord and the cavities: third ventricule, mesencephalic aqueduct, fourth ventricle and central canal in spinal cord were observed. With 90 days, the main structures were identified: (1) cerebral hemispheres, corpus callosum and fornix, of the telencephalon; (2) interthalamic adhesion, thalamus, hypothalamus and epythalamus (glandula pinealis), of the diencephalon; (3) cerebral peduncles and quadruplets bodies, of the mesencephalon; (4) pons and cerebellum, of the metencephalon; (5) medulla oblongata or bulb, of the myelencephalon; and (6) spinal cord, of the primitive spinal cord. After 110 days of gestation, the five encephalic vesicles and its structures were completely developed. It was noted the presence of the spinal cord with the cervicothoracic and lumbossacral intumescences. In summary, the results describes the formation of the neural tube from the neural plate of the ectoderm, the encephalic vesicles derived from the neural tube and subsequent structural and cavities subdivisions, thus representing the complete embryology of the central nervous system.(AU)

Os estudos que descrevem o desenvolvimento do sistema nervoso central (SNC) são de suma importância para compreensão da organogênese e identificação dos prováveis eventos que resultam em malformações congênitas. Estes dados podem subsidiar novas pesquisas relacionadas ao desenvolvimento normal, e interpretação de malformações e alterações que ocorrem ao longo da organogênese do SNC, considerando neste momento a necessidade de estudos preliminares em modelos animais, os quais poderiam ser utilizados para pesquisas experimentais sobre a influência de agentes infecciosos como o Zika vírus, no desenvolvimento do sistema nervoso e suas relações com a microcefalia em humanos recém-nascidos. O presente estudo teve como objetivo descrever os aspectos morfológicos macro e microscópicos da organogênese do SNC de bovinos, buscando correlacionar os achados morfológicos com a idade gestacional. Todos os animais foram mensurados para detectar o período gestacional. Foram coletados e analisados 14 embriões e nove fetos de bovinos de diferentes idades gestacionais. No embrião bovino a partir do décimo sétimo dia de gestação, encontra-se a formação do tubo neural, o neuroporo cranial e neuroporo caudal, e formação dos somitos. Após 24 dias de desenvolvimento, são observadas na parte cranial do tubo neural cinco vesículas encefálicas denominadas: telencéfalo, diencéfalo, mesencéfalo, metencéfalo e mielencéfalo; e na parte caudal do tubo neural, encontra-se a medula espinhal primitiva. Entre 90 a 110 dias de gestação, observa-se a total diferenciação das cinco vesículas do SNC. Com 90 dias, são identificas as principais estruturas: (1) do telencéfalo, os hemisférios cerebrais, corpo caloso e fórnix; (2) do diencéfalo, a aderência intertalâmica, tálamo, hipotálamo e epitálamo (glândula pineal); (3) do mesencéfalo, os pedúnculos cerebrais e os corpos quadrigêmios; (4) do metencéfalo, a ponte e o cerebelo; (5) do mielencéfalo, a medula oblonga (ou bulbo); e (6) da medula espinhal primitiva, a medula espinhal. Após 110 dias, as cinco vesículas encefálicas e as suas subdivisões se encontram completamente desenvolvidas. Notou-se a presença da medula espinhal com as intumescências cervicotorácica e lombossacral. Em resumo, os resultados demonstram a formação do tubo neural a partir da placa neural do ectoderma, as vesículas encefálicas provenientes do tubo neural e posteriormente as subdivisões das estruturas e das cavidades, que representam a completa embriologia do sistema nervoso central.(AU)

Distribuição do nervo fibular comum em fetos de equinos e descrição anatômica de pontos para bloqueio anestésico / Distribution of common peroneal nerve in equine fetuses and anatomical description of sites for anesthetic block

Analisou-se a distribuição do nervo fibular comum em 30 fetos de equinos, sem raça definida, provenientes do acervo do Laboratório de Anatomia Animal da Faculdade de Medicina Veterinária da Universidade Federal de Uberlândia, que foram injetados e conservados em solução aquosa de formaldeído a 10%. Contatou-se que o referido nervo deriva do isquiático, divide-se em nervos fibulares superficial e profundo, distribuindo-se para os músculos extensores lateral e longo do dedo, fibular terceiro e tibial cranial. Traçando-se uma linha imaginária na região médio-lateral da tuberosidade do osso tíbia, o nervo fibular comum pode ser bloqueado em sua parte proximal, no terço caudal, entre o tendão de inserção do músculo bíceps femoral e a face lateral do músculo gastrocnêmio lateral (terço médio); e o nervo fibular profundo, na parte proximal da tíbia, crânio-distalmente ao fibular comum. O bloqueio do nervo fibular superficial pode ser realizado em duas regiões da tíbia: na proximal, considerando-se a linha imaginária, distalmente ao ponto citado para o fibular comum e caudalmente ao descrito para o fibular profundo; e na distal, na face lateral da articulação tíbio-társica, entre os tendões de inserção dos músculos extensores lateral e longo do dedo.

The distribution of the nervus fibularis communis was analyzed in 30 equine fetuses, mongrel, from the collection of the Animal Anatomy Laboratory at the School of Veterinary Medicine of Universidade Federal de Uberlândia, which were injected and stored in an aqueous solution of 10% formaldehyde. It was found that this nerve emerges from the ischiadicus, divides itself into nervus fibularis profundus and nervus fibularis superficialis distributing to the musculi extensor digitorum lateralis, extensor digitorum longus, fibularis tertius, and tibialis cranialis. Drawing an imaginary line in the medial-lateral region of the tuberositatis tibia, the nervus fibularis communis may be blocked in its proximal portion, in the caudal third, between the tendon of insertion of the biceps femoris and the lateral side of the musculus gastrocnemius (medium third); and the nervus fibularis profundus may be blocked in the proximal tibia, cranio-distally to the nervus fibularis communis. The block of nervus fibularis profundus may be performed in two regions of the tibia: proximal, considering the imaginary line, distal to the site referred to the nervus fibularis communis, and caudal to that described for the nervus fibularis profundus; and distal, on the lateral side of the tibiotarsal joint, between the tendons of insertion of the musculi extensor digitorum lateralis and extensor digitorum longus.

Macroscopic and microscopic analysis of the tongue of the common opossum (Didelphis marsupialis).

We performed a macroscopic and microscopic study of the tongues of common opossums, Didelphis marsupialis, from South America. We studied two males and two females. We collected morphometric data on the tongue with precision calipers. For the light microscopy and scanning electron microscopy analyses, we fixed tissue fragments in 10% formaldehyde and 2.5% glutaraldehyde, respectively. The opossum tongues averaged 5.87 ± 0.20 cm in length, 3.27 ± 0.15 cm in width at the lingual body, and 3.82 ± 0.15 cm in width at the root. The mean thickness of the lingual body was 1.8 ± 0.1 cm, and the thickness of the root was 3.82 ± 0.15 cm. Sharp filiform papillae were scattered across the entire tongue; conical filiform papillae occurred on the lingual body and tongue tip; fungiform papillae were scattered among the filiform papillae on the lingual body and tongue tip; and there were three vallate papillae at the root of the tongue. We found two strands of papillary projections in the tongue root. Despite the low variability observed in the lingual papillae, the morphological data obtained in this study may be related to the opossum's diverse food habits and the extensive geographic distribution of the species throughout America.